Using Android AutoCompleteTextView with ArrayAdapter<Objects> instead of ArrayAdapter<Strings>

Question

I wanted to use AutoCompleteTextView in my android application.I know how to use it with simple array of Strings, but I wanted AutoCompleteTextView to use list of Objects to perform completion.My code for this is following:

ACTIVITY CODE

public void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.search);

        initialize();
        ArrayAdapter<Student> adapter = new ArrayAdapter<Student>(this,
                R.layout.dropdown_list_item, GetAllStudentsList());

        searchBox.setAdapter(adapter);
        searchBox.setThreshold(THRESHOLD_VALUE);
        searchBox.setTextColor(Color.BLACK);
}

searchBox.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> adapterView, View view,
                int position, long arg3) {
                     //Here i will grab the Student object that user selected from drop-down

        }

    });

public ArrayList<Movies> GetAllStudentsList() {

//This method returns a ArrayList of <Student> type objects
}

Student class Object has information regarding a student which is ID,NAME,ADDRESS,MARKS.

I know AutoCompleteTextView needs an array of String type object to perform search operation.In my case I want AutoCompleteTextView to use my ArrayList to perform completion on the basis of Student object field NAME.I dont know how should I specify AutoCompleteTextView to use NAME field of Student object.Please help me providing any Link or a small example.

Thanks

Bean

I guess I need to make Custom AutoCompleteTextView and override some methods.. – Bean

Answer 1

Two ways:

1. Override toString() in Student class and make it return name. You can get the object that was selected with the following code:

    public static class Student {
   
       private String name;
   
           public Student(String name) {
               this.name = name;
           }
   
           @Override
           public String toString() {
               return name;
           }
   
       }
   
   AutoCompleteTextView tv = (AutoCompleteTextView) findViewById(R.id.autoCompleteTextView1);
   final ArrayList<Student> list = new ArrayList<MainActivity.Student>();
   list.add(new Student("Viru"));
   list.add(new Student("Gauti"));
   ArrayAdapter<Student> adapter = new ArrayAdapter<MainActivity.Student>(
           this, android.R.layout.simple_dropdown_item_1line, list);
   tv.setAdapter(adapter);
   
   tv.setOnItemClickListener(new OnItemClickListener() {
   
       @Override
       public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
               long arg3) {
           Student selected = (Student) arg0.getAdapter().getItem(arg2);
           Toast.makeText(MainActivity.this,
                   "Clicked " + arg2 + " name: " + selected.name,
                   Toast.LENGTH_SHORT).show();
       }
   });
   

2. Implement a custom adapter (by extending BaseAdapter class or ArrayAdapter<Student> class) Check this tutorial : http://www.ezzylearning.com/tutorial.aspx?tid=1763429

Toneme

if I use toString() then when user selects an item from drop-down I wont get Object but the String and then I would i have to search the object using that String, right? – Bean

You get the selected index. You can use that to get the object. – Toneme

Selected index of dropdown and AutoCompleteView will be using the String representation of Objects not actual objects? – Bean

simple and understandable :) the best example I saw. – Chitchat

I think this post answers the question in the best way, however: a) What is tv.setOnItemClickListener for? b) If you use Students for the adapter as presented, then the auto-suggestion box appears with the list of strings. How to render the other things in the auto-suggestion box (e.g. the student's image)? – Theresita

It was the toString() !! Thank the cheese's – Gautea

Answer 2

You can use an AbstractList to get the String representation of each item in your object list.

private void setupAutoComplete(AutoCompleteTextView view, List<T> objects) {
    List<String> names = new AbstractList<String>() {
        @Override
        public int size() { return objects.size(); }

        @Override
        public String get(int location) {
            return objects.get(location).getName();
        }
    };

    view.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, names));
}

Phagy

This is a better answer as you do not modify the POJO for a view! – Varela

Answer 3

You can override getItem in this adapter, depend on each type to convert it into String

 override fun getItem(position: Int): String? {
        val item = listData[position]
        when (item) {
            is BankItem -> {
                return item.bankName
            }
        ....
 }

Hydro